Flight #: 15 Date: 3rd of November, 2002 Venue: EARS, Elsworth, Cambridgeshire R-DAS Type: R-DAS Compact R-DAS firmware: 3.2 R-DAS Recorded Altitude: 1435 feet (435 metres) Apogee - Charge Firing Delta-t: 0 seconds Apogee - Charge Firing Delta-h: 0 feet (0 metres) Descent Rate at Apogee Deployment: 0 feet per second (0 metres per second) R-DAS Flight Mode: Apogee & Main Ejection (breakwire launch detection & smart recovery) Total Time of Flight: 60 seconds Apogee - Charge Firing h Variance: 0% Launch Vehicle Diameter: 2.6 inches Launch Vehicle Length: 6 feet Launch Vehicle Propulsion: Hypertek I-205 Hybrid 330/54-125-J (0.125 injector orifice) Fins: 3 clipped swept deltas (Aerofoiled) Launch System: Rail Launch Finish: Semi-painted Ejection Method: Electronic Deployment using apogee charge in SafeEject canister, then main charge in SafeEject canister Ejection Ignition Type: Daveyfire igniters (electric matches) Launch Vehicle Mass: 2.5 kg (vehicle with hybrid motor but no oxidiser loaded) Total Propellant Mass: 298 grams Total Loaded Motor Mass: 1067 grams Total Impulse: 470 Newton seconds Optimum Theoretical Burn Time: 2.40 seconds Actual Useable Burn Time: 3.10 seconds
Comments The fifth flight of the Hephaestus rocket, launched on the Hypertek I-205 hybrid rocket motor (using a 330cc oxidiser tank and a standard fuel grain). The rocket followed a standard hybrid trajectory with weathercocking on the ascent, with the Compact R-DAS firing the SafeEject fitted ejection charges on cue, and the rocket recovering safely and intact. The Compact R-DAS used breakwire launch triggering with smart recovery. As with previous Hypertek hybrid launches, this option was again chosen because the oscillation in Hypertek motor combustion has been known to result in irregular launch triggering of the R-DAS. The breakwire and smart recovery option worked perfectly, and both ejection channels fired at correct times. A breakwire from Airborne Engineering Limited was fitted again, and 1 loud sounder was also carried on the flight.
Thrust Section of Flight